Stop mechanism for grain-elevators



(No Model.)

J. A. MGLENNAN.

STOP MECHANISM FOR GRAIN ELEVATORS. No. 262,453. Patented Aug. 8, 1882.

.713/171 uZ/WFZ @2212 an ult oivugs UNITED STATES PATENT OFFICE.

JOHN A. MGLENNAN, OF CHICAGO, ILLINOIS.

STOP MECHANISM FOR GRAIN-ELEVATORS.

SPECIFICATION forming part of Letters Patent No. 262,453, dated August8, 1882.

Application filed April 2, 1881. (No model.)

To all whom it may concern:

Be it known that I, JOHN A. MCLENNAN, a citizen of the United States,residing in the city of Chicago, in the county of Cook, in the State ofIllinois, have invented a certain new and useful Improvement in StopMechanism for Grain-Elevators, which is fully set forth in the followingspecification,reference being bad to the accompanying drawings, inwhich- Figure 1 is side elevation of the upper part of a grain-elevatorprovided with my improvements. Fig. 2 is an end elevation of the same,the extreme upper part being broken away, and one pair of uprighttimbers being removed, so as to give an unobstructed view. Fig. 3 is adetailed and enlarged side elevation, showing the cam and levers whichconstitute the principal part of my improvement, the first lever beingbroken away toward the end to which the power is applied.

The same letters denote the same parts in all the figures.

My invention relates to elevators for the transfer of grain between thestore-house and the car or vessel and for analogous purposes; and itconsists in an improved device for arresting the operation of theelevator by means of a combination of levers with a rocking arm, such asI will proceed to describe fully, the op- 0 ject being to provide a stopmechanism more efficacious, less expensive, and less liable to get outof order than those now in use.

In the drawings, A and A denote respectively the front and rear pairs ofupright timbers supporting the pulley G, which raises and lowers thebuckets. This pulley has its immediate bearings in the boxes 0, in whichits shaft 0 turns. These boxes rest on the horizontal beams B, which arepivotally supported at b in the rear upright timbers and rest in slots ain the front uprights, which slots are vertically somewhat larger thanthe horizontal beams, so as to admit of lifting the forward ends of thelatteralittleway. Thefriction-wheelD,which communicates motion to thecarrying-pulley in the usual way, is supported, like it, by means of itsshaft D, turning in the boxes d, which rest on the fixed horizontalbeams B. When for any reason it becomes necessary to stop the motion ofthe carrying-pulley it is done by raising the forward ends of thehorizontal beams B, so as to lift it out of contact with thefriction-wheel D, the slots a being deep enough to admit of this.

All the parts thus far described are in familiar use; and I do not claimany of them as my invention, which consists solely in the improvedmechanism for lifting the horizontal beam B.

To the front edges of the front upright timbers, A, are affixed bracketsE, which afford bearings for a rotating shaft, F. In front of eachupright timber, and on the inner side of the corresponding bracket,rocking arm G is rigidly afiixed to the shaft. This arm projects in theopposite direction from the upright timber A, and near its outer end, atg, is pivoted the lower end of a connecting-bar, H, whose upper end ispivoted on the lower side of the corresponding horizontal beam, B, at apoint, h, perpendicularly above the point g in the axis of the shaft F,and therefore nearer to the upright timber than the lower end, exceptwhen the outer end of the rocking arm is also perpendicularly above theaxis of F. The length of the rocking arm is such as to allow the outerend of the latter to fall nearly into a horizontal line with the center{1, the timber B then resting in the bottom of the slot at and thecarrying-pulley being in contact with the frictionwheel D, so that themotion of the machinery will be communicated to the carrying-pulley. Anyturning of the shaft F in such a direction as to elevate the outer endof the rocking arm must obviously increase the vertical distance betweenthe upper and lower ends of the bar H, and thus necessitate the liftingof the corresponding end of the bar B, the length of the rocking armbeing sufficient to insure the lifting of the carrying-pulley clear ofany contact with the friction-wheel, and thus to disconnect the formerentirely from the driving machinery. Such a turning of the shaft F isefiected at pleasure by means of the lever J, which is set on one end ofthe shaft by means of an eye at one of its ends, and. is rigidly affixedthereto, the place of attachment being on the outer side of the nearestupright timber A, as shown in Fig. 2, allowing room for a lever of anydesirable length to be turned without obstruction. A cord, J, attachedto the farther end of the lever, extends downward to the floor, where Vthe operator is stationed. By pulling on the cord the shaft F is turned,and with it the rocking arm G. instantly thrusting the upper end of thebar H upward, and thus lifting the horizontal beam B, which supports thecarrying-pulley O.

At present the lifting of the beam B is ordinarily effected by means ofa lever of the second kind, pivoted on the front of the beam A above Band connected with the latter by a strap, so that the lifting of theouter end of the leverlifts the horizontal beam. Ofcourse the cord bywhich this end of the lever is brought under the control of an operatoron a lower floor must first pass upward and over a pulley, and thelength of the lever is necessarily limited by its position in front ofthe elevator. In practice a crank is usually apt he lever.

ratus which I have described, a direct pull on the cord with one handreadily lifts the carry ing-pulley out of contact with thefrictionwheel, the power requisite being hardly more than one per cent.of that which must be applied to the outer end of the upper lever of thedevice now in use. Moreover, the improved device which I have describedcan be constructed and put in place for about fifteen per cent. of thecost of the other, and when in place is not nearly so liable to get outof order.

What I claim as myinvention, and desire to secure by Letters Patent, is-

In a grain-elevator, the combination of the pivoted horizontal beam Bwith the doubly pivoted bar H, rocking arm Gr, shaft F, and lever J,substantially as and for the purpose described.

JOHN A. MGLENNAN.

Witnesses:

THOMAS H. PEASE, GEO. R. CUTLER,

